WILLIAMSTOWN — “The whole Clark experience has been transformed.” So says Michael Conforti, since 1995 the director of the Sterling and Francine Clark Art Institute in the Berkshires.

His announcement will make many people uneasy. Going to the Clark has long been one of the great museum-going experiences. Situated in Williamstown, right by Williams College, the Clark opened in 1955, six years after its founders, Sterling and Francine Clark, first visited the town.

It occupies its own beautiful campus with rolling meadows and forested slopes streaked with walking trails, punctuated by splendid views. It’s an ideal setting for the museum’s collection, which is rich in 19th-century French painting and sculpture but sprinkled, too, with masterpieces of European art from earlier periods, as well as 19th-century American art.

Why mess with any of this? What could possibly be improved?

On July 4, when the Clark reopens after a new building and renovation project that cost over $100 million, and coincided with the Clark sending the core of its collection on a multi-venue world tour seen by millions, we can all find out.

The Sterling and Francine Clark Art Institute reopening

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The Clark’s mission was always to be more than just a suite of spacious, well-stocked galleries. It doubles as a center for education and research, including conservation. And, under Conforti, it has also been a venue for increasingly ambitious temporary exhibitions.

These have not only grown in size; their focus has been gradually shifting beyond the Clark’s traditional comfort zone — the 19th century — and into the 20th and even 21st centuries.

Plans to expand the museum’s space for temporary exhibitions, and to get its back-of-house facilities in line with accepted standards, slowly morphed, explains Conforti, into a more ambitious attempt to “change the whole campus experience.”

In 2009, a new building, the Stone Hill Center, opened a short walk uphill from the Clark’s main museum buildings. Designed by Japanese architect Tadao Ando, it houses several galleries, and a sophisticated conservation center.

That was just the first step. Unrestricted by any Isabella Stewart Gardner-style will limiting what he can and can’t do with the Clark, Conforti had bigger plans. He hired Ando to design a new visitors center, combined with exhibition galleries, a conference center, a cafe, and a shop.

Perched beside a large pond that helps to unify the stylistically dissonant preexisting buildings, the new Ando structure — which Conforti describes as very discreet (“you don’t really see it, you walk through it”) — leads visitors directly into the original 1955 building. This building, which is filled with galleries for the permanent collection, has meanwhile been overhauled by Annabelle Selldorf of Selldorf Architects in New York.

The Ando building is obviously the big news; it’s the one new structure. But according to Conforti, the big surprise of the whole project has been “how good the Selldorf component is. What she has done is give [the old building] a kind of gravitas.”

The campus itself, meanwhile, has been significantly revamped by landscape architect Gary Hilderbrand,
of Reed Hilderbrand Associates, a firm based in Watertown, working together with Ando. “We had acreage and views before,” explains Conforti, “but not a landscape that made the most of them.”

Tadao Ando Architect & Associates

The visitors center, designed by architect Tadao Ando.

The changes will be felt as soon as you arrive. A new entrance drive, with views onto the mountains and a lily pond, will sweep visitors into a landscaped car park. The pond between the buildings will act as a self-sustaining reservoir, reusing storm water for plumbing and irrigation, part of a coordinated water management system that includes large-scale rainwater collection and a series of constructed wetlands, rain gardens, and infiltration meadows.

The wonderful walking trails have also been extended and enhanced, and more than 350 native trees have been planted.

Selldorf has also overhauled the Manton Research Center, an unattractive building that opened in 1973 to house the research library, the administrative offices, and a spacious reception area — although that work won’t be finished until later in the year. In its new incarnation, it will be dominated by a big public reading room, flanked by galleries devoted to prints and drawings and to the Manton Collection of British Art.

Where did the more than $100 million spent on the project come from? According to Conforti, more than 250 people have contributed, but $50 million has come from a single source: the Manton Foundation.

Sir Edwin Manton was a British businessman who was the driving force behind the establishment of the insurance corporation AIG, or American International Group. He was a major collector and philanthropist, who, apart from Sir Henry Tate, was the most important benefactor to London’s Tate Gallery in that institution’s history.

Tadao Ando Architect & Associates

The center’s lower level.

Manton died in 2005, and virtually out of the blue, his foundation gave over 200 paintings, drawings, and prints by British artists to the Clark in 2007. It has subsequently underwritten a building project which might have been difficult to pull off, concedes Conforti, without Manton money.

The Clark will launch its new incarnation with three temporary exhibitions. One will be a show of art made between 1950 and 1975. Called “Make It New: Abstract Painting From the National Gallery of Art 1950-1975” and installed in the new Tadao Ando building, it will feature Jackson Pollock’s “Number 1, 1950 (Lavender Mist),”
and works by Mark Rothko, Lee Bontecou, Jasper Johns, Cy Twombly, Yayoi Kusama, and many others. Coinciding with renovations to the modern wing at the National Gallery
of Art in Washington, D.C., the show will be organized by Harry Cooper, curator of modern art at the National Gallery, and the Clark’s David Breslin.

The National Gallery will also be supplying work to “Raw Color: The Circles of David Smith.” Featuring nine sculptures and two paintings from, or related to, the great American sculptor’s “Circle” series (1962-63), the show will situate these vibrantly colored sculptures, last united at the National Gallery’s Smith retrospective more than 30 years ago, against the verdant backdrop around the Stone Hill Center.

A third exhibition will be “Cast for Eternity: Ancient Ritual Bronzes,” a selection of more than 30 objects, including many bronze vessels and bells dating from China’s bronze age, from the Shanghai Museum.

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